Review of ACT 6 Puck HD Clutch @ Pure Automotive Performance
 

Hey guys, just a quick review of my experience with a clutch install I did this week for a customer. I know when it comes to all the different options for parts, there's a lot of speculations and assumptions of prospective options. This is a TOTALLY UNBIASED review. I don't make any more money from selling you an ACT Clutch than I do from a Comp Clutch, Clutchmasters, etc. I just wanted to post my thoughts on this clutch so if you're shopping clutches you have some real world opinions to go off of.

ACT (Advanced Clutch Technologies) 6 Puck HD

What ACT Says:
This Performance Race Kit features ACT's most popular Heavy Duty Pressure plate. ACT Heavy Duty pressure plates use exclusive diaphragm design to increase clamp load, reduce deflection and maximize clutch life. All diaphragms endure an exclusive four-stage, heat-treating process for unparalleled performance. ACT pressure plates have precision cover stampings to provide rigidity and consistency. ACT's 6-pad rigid race discs are made with high quality, ceramic friction materials. The chrome-moly hub is heat-treated for strength and durability. The lightweight, rigid design allows for quicker shifts and smooth, trouble-free service. With the 6-pad rigid race disc engagement is harsher, but shifting is fast. The 6-pad rigid race disc is recommended for larger clutch sizes to absorb more heat.

The SB8-HDR6 Includes the Following Components

SB-017 - Heavy Duty Pressure Plate - Clamp load increase of 70%, Pedal feels stock to moderate, SFI Certified to insure safety.

6224018 - Solid 6-Puck Disc - Aggressive engagement with fast shift action; Lightweight rigid design for low to moderate gear rattle. Recommended for high horsepower street or race use.

600700 - Prolite Flywheel - Lightest flywheel offering with lowest inertia, preferred for road racing or rally racing, and have reduced drivability.

RB004 Release Bearing OEM Quality Throw out Bearing

PB1004 Pilot Bearing OEM Quality Pilot Bearing

AT90 Alignment Tool For Quick and Easy Installation
TQ Capacity 345 ft/lbs

What I say:

The install wasn't a terrible experience, the pressure plate is tricky to get seated because there are multiple dowel pin holes but it only properly seats one way. The pressure plate to clutch disc clearance was tight, I had to very gradually work it into place to get it lined up properly.
The parts are all high quality, the release bearing and pilot bearing are nearly identical to stock. The flywheel is pretty gnarly looking as it is only 10.5 lbs. It uses the stock flywheel bolts, but comes with new pressure plate mounting bolts.

Driveability:
The pedal had to be adjusted up quite a bit from the "DIY better engagement" setting in order to feel proper. The engagement is very quick, you don't really have the large amount of play that the stock clutch has. It's not the most aggressive clutch I've ever driven, but it took a little playing around to get the hang of. The pedal feel is, in my opinion, mildly firm. It definitely takes more effort than stock, but I don't think it would cause any leg cramps if you were stuck in traffic. Upon the first test drive, I found that it takes a little more gas when shifting from a stop in order to prevent jerky starts. That got easier as I drove it around and got the feel for it. You can really feel the quick engagement when you are doing a little spirited driving and shifting quickly. It makes the gear changes much faster that stock. There is a soft rattle or vibration noise that reverberates as you decelerate in gear. It is not offensive at all, I was listening for it because its common in lightened flywheels. Had I not been listening for it, I probably wouldn't have noticed for a while. If you've ever had a lightweight flywheel, you know what I mean when I say, you can feel the lack of inertia in low RPMS. For those that don't know what I mean, the lightened flywheel doesn't maintain rotational inertia as well as the heavier stock one, so when you're coming to a stop, the RPMS fall off quickly, causing a slight dip. This effect is completely normal when you go with a lightened flywheel. The upside is that, as quickly as the RPMS fall off, it revs up that much faster. 10 Miles later, no check engine light, no issues reported. Its not my vehicle so I won't be putting any more miles on it than that. Here are some comparison pics:
http://i1273.photobucket.com/albums/...ps9afa26a7.jpg

Thanks For Reading!

Brady @Pure Automotive Performance

Thanks for taking the time to post this and give your impressions. Did you happen to weigh the stock versus ACT setup?

Just a couple additional points for those that don't have a bunch of diverse clutch experience:

*The install photos appear to be the SB8-HDG6 kit, which is a sprung disc.
*Sprung discs make everyday drivability much easier as there's a tiny bit of compliance during engagement.
*Segmented discs make everyday driving tougher as the clutch ends up being more like an On/Off switch instead of having a take-up zone. The fewer the segments, the harder the On/Off switch.
*For a daily driven street car, a solid sprung disc is the wisest choice, without question.
*ACT offers the "HDSS" clutch kits, which are rated for 270 LbFt, which is more than all the stage 1 turbo kits on 91 octane running sane boost levels.

I hope that helps,
Ryan

This flywheel was 10.5 lbs. I didn't weight the stock one.
This is the sprung disc and I appreciate you taking the explanation further, I forgot to mention that is is sprung. I would never sell an unsprung clutch to someone who daily drives their car, its just not worth it.
This kit is rated to 345 lbft, the customer went that route because he plans on using e85 with his turbo setup and he wanted to be well below the torque limit.

Would getting the lightweight flywheel only and putting it on with the stock clutch plate work or does a person need to do the clutch too? I'll never be running more hp than the stock clutch can handle since I'll eventually only be doing stage 1 twin screw supercharger, so just wondering.

More importantly than the feel and noise, have you tried shifting at redline in multiple gears?

The ACT on my Evo sucks hard at high rpm shifts, successfully locking me out of any gear if I try to shift after 6k rpm.

-Acree

I've seen and ACT Streetlite Flywheel which is 12 lbs and a Prolite which is 11 lbs and I believe SPEC makes a 13 lb version. Those are designed to work with the stock clutch assembly.

In the short distance I drove it I wound out 2nd and 3rd and had no issues shifting. But again, I haven't driven it much as it is not my car.

I have about 1000 miles on the same clutch, and I have to say his review is pretty spot on. I have had no issues thus far. Clutch pedal is definitely noticably stiffer than OEM, but not nearly as bad as some cars I have driven. I felt the take up point was perfect where it was, as set from the factory (I have never done the DIY adjustment). You definitely want to take off from a stop with at least 1500 revs or you will get shaking and probably stall. There is noticeable chatter at idle around 700 RPM along with some other strange sounds at times when driving between 1000 and 2000 RPM. I have definitely gotten used to it over the last month. I purchased new OEM flywheel bolts from my local Suby dealer for around $25, and I used red loctite on them along with using it on the ACT supplied pressure plate bolts as I definitely don't want them coming out.

Dude... you're such a copy cat... Thanks for posting the review of the clutch Brady! Can't wait to try it out tomorrow morning!

Would like to see how long these puck clutches last being street driven.

I think you have that reversed. :D

I have this clutch and hate it. The noise at idle makes me, other people at red lights and anyone I take for a ride look at me funny or ask "what's that rattle?" The engagement is far to rough and touchy. Gear shifts are rough as hell from 1st to 2nd. I will happily change clutches the second I wear this one out. Which, since I drive the car so sparsely might be a minute.

If you can, save yourself the head ache and wait for a regular (non puck) style clutch with the holding capacity. I for one am looking forward to such a clutch. Hopefully it comes soon.